It seems that Zeus was preparing a wedding banquet for Peleus and Thetis and did not want to invite Eris because of Her reputation as a trouble maker.*

    This made Eris angry, and so She fashioned an apple of pure gold** and inscribed upon it KALLISTI ("To The Prettiest One") and on the day of the fete She rolled it into the banquet hall and then left to be alone and joyously partake of a hot dog.

    Now, three of the invited goddesses,*** Athena, Hera, and Aphrodite, each immediately claimed it to belong to herself because of the inscription. And they started fighting, and they started throwing punch all over the place and everything.

    Finally Zeus calmed things down and declared that an arbitrator must be selected, which was a reasonable suggestion, and all agreed. He sent them to a shepherd of Troy, whose name was Paris because his mother had had a lot of gaul and had married a Frenchman; but each of the sneaky goddesses tried to outwit the others by going early and offering a bribe to Paris.

    Athena offered him Heroic War Victories, Hera offered him Great Wealth, and Aphrodite offered him the Most Beautiful Woman on Earth. Being a healthy young Trojan lad, Paris promptly accepted Aphrodite's bribe and she got the apple and he got screwed.